Foam-holding agent and utilization thereof

ABSTRACT

The present invention provides a foam-holding agent which has a sufficient foam-holding property and is satisfactory with regard to safety, taste, aroma and other properties required for foods, as well as providing effervescent drinks or forming beverage comprising the foam-holding agent. More specifically, the present invention is directed to a foam-holding agent for effervescent drinks or forming beverage, which comprises a tea leaf extract obtained by preparing tea in a standard manner from leaves of black tea, green tea, oolong tea,  Gynostemma pentaphyllum  tea, Mate tea, Pu-erh tea, barley tea,  Coix lacryma - jobi  var.  ma - yuen  tea, brown rice tea,  Houttuynia cordata  tea or other tea leaves, and then extracting catechin-rich components using a solvent such as water and/or ethanol. The present invention is also directed to effervescent drinks or forming beverage characterized by comprising the above foam-holding agent, which have excellent foam-producing and foam-holding properties and also provide dense and smooth-textured foam.

FIELD OF THE INVENTION

The present invention relates to foam-holding agents available for usein drinks. The present invention also relates to carbondioxide-containing drinks having foam-producing and foam-holdingproperties. The present invention further relates to carbondioxide-containing drinks having a beer-like effervescence without usinga fermented grain liquor as a source material.

PRIOR ART

Fermented grain liquors are alcoholic drinks produced bysaccharification and yeast fermentation of grain-derived starch. Carbondioxide-containing fermented grain liquors (e.g., beers, sparklingliquors) will generate foam to prevent the escape of carbon dioxide fromthe liquors when poured into glasses or the like before being drunk,thereby maintaining refreshing qualities of the drinks. Such foam isalso effective in retaining sensory components (taste and aroma).Moreover, dense and smooth-textured foam will prevent the oxidation ofcontents and maintain the freshness of drinks.

On the other hand, there have also been proposed effervescent drinks orforming beverage employ a foaming agent as an ingredient acting toimprove effervescence and further employ a foam-holding agent as aningredient acting to ensure long-term holding of the generated foam.

Known examples of such drinks include effervescent mixed liquors whichcontain a saponin component (JP 61-88869 A); effervescent drinks orforming beverage which contain saponin or a saponin-containingpreparation and a thickener (e.g., oligosaccharides such as linearmaltose oligosaccharides or branched isomaltose oligosaccharides, or acombination of oligosaccharides and polysaccharides) (JP 5-38275 A);carbon dioxide-containing alcoholic drinks which contain ahop-containing fermented malt liquid, a foaming agent, and afoam-holding agent serving as a viscosity stabilizer (e.g., agar,gelatin, xanthan gum, carragheenan, pectin, tamarind gum, gellan gum,Locust bean gum) (JP 11-299473 A); and carbon dioxide-containingalcoholic drinks which contain a hop-containing fermented grain liquidand a foaming agent, either alone or in combination with a foam-holdingagent serving as a viscosity stabilizer (JP 2001-103954 A).

However, these drinks do not have a sufficient foam-holding property andare not satisfactory with regard to safety, aroma and other propertiesrequired for foods.

SUMMARY OF THE INVENTION

As a result of extensive and intensive efforts made to provideeffervescent drinks or forming beverage which have a sufficientfoam-holding property and are satisfactory with regard to safety, aromaand other properties required for foods, the inventors of the presentinvention have surprisingly found that, when using a water and/orethanol extract of tea leaves, effervescent drinks or forming beverageexert an excellent foam-holding effect. This finding led to thecompletion of the present invention.

The foam-holding agent of the present invention allows a reduction ofthe amounts of additives and hop extract used as foam-producingmaterials and also imparts practical foam-producing and foam-holdingproperties to carbon dioxide-containing drinks at low cost. Moreover,the use of the foam-holding agent of the present invention not onlyenables a wider range of aromas, but also enables the production ofcarbon dioxide-containing drinks having a beer-like effervescencewithout using a fermented grain liquor.

Namely, the present invention provides a foam-holding agent availablefor use in drinks, which has a sufficient foam-holding property andensures the safety required for foods.

The present invention also provides a carbon dioxide-containing drink,which is excellent in refreshing quality and texture on the throat(“nodogoshi” or easiness to drink) imparted to effervescent drinks orforming beverage, which has a good foam-holding property, and which isalso satisfactory with regard to safety, aroma and other propertiesrequired for foods.

The present invention further provides a carbon dioxide-containingdrink, which has excellent foam-producing and foam-holding propertieswithout using a fermented grain liquor as a source material.

The present invention enables the provision of carbon dioxide-containingdrinks having a taste and atmosphere suggestive of beer, as judged bytheir appearance.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a foam-holding agent comprising a waterand/or ethanol extract of tea leaves. The present invention also relatesto a carbon dioxide-containing drink characterized by comprising (A) afoaming agent and (B) a water and/or ethanol extract of tea leaves.

The present invention provides a novel foam-holding agent.

The foam-holding agent of the present invention may use a tea leafextract prepared by extracting catechin-rich components from tea leavesusing a solvent such as water and/or ethanol in a standard manner.

The resulting extract may further be concentrated for use as a tea leafextract.

In the present invention, tea leaves may be those of non-fermented tea,semi-fermented tea, fermented tea or the like. Examples include leavesof black tea, green tea, oolong tea, Gynostemma pentaphyllum tea, Matetea, Pu-erh tea, barley tea, Coix lacryma-jobi var. ma-yuen tea, brownrice tea and Houttuynia cordata tea, as well as leaves of other plantsintended for drinking.

A tea leaf extract used as the foam-holding agent of the presentinvention is preferably an extract of black tea, green tea or oolong teain consideration of its influences and contributions as a foaming agentto stability of aroma and quality, as well as in consideration ofavailability costs.

A solvent used for extraction may be water alone or any mixture of waterand ethanol, but it is preferable to use water alone or a mixture withwater.

The ratio between tea leaves and a solvent during extraction is notlimited in any way, but the solvent is preferably in 2- to 1000-foldexcess (by weight) over tea leaves, particularly in 5- to 100-foldexcess (by weight) over tea leaves in terms of handling and efficiencyof extraction. The extraction temperature is conveniently set in therange of from room temperature to the boiling point of the solvent undernormal pressure. The extraction time will vary depending on theextraction temperature, but it is preferably set in the range of from 10minutes to 24 hours.

To concentrate the tea leaf extract thus prepared, the resulting extractmay further be treated in a standard manner by heating under reducedpressure to remove water. Alternatively, this extract may be treatedwith a synthetic adsorbent. Examples of a synthetic adsorbent used forseparation of tea leaf extract include aromatic synthetic adsorbentsprepared by polymerizing styrene and divinylbenzene or methacrylatesynthetic adsorbents prepared by polymerizing methacrylic acid.Commercially available products for aromatic synthetic adsorbentsinclude Diaion HP20, Diaion HP21 (Mitsubishi Chemical Corporation),Amberlite XAD2 and Amberlite XAD4 (Rohm and Hass, USA), whilecommercially available products for methacrylate synthetic adsorbentsinclude Diaion HP1MG, Diaion HP2MG (Mitsubishi Chemical Corporation),Amberlite XAD7 and Amberlite XAD8 (Rohm and Hass, USA).

Treatment with a synthetic adsorbent is preferably accomplished byfilling the adsorbent into a column, passing a tea leaf extract throughthe column and then washing the resin with water. When a tea leafextract is treated with such a synthetic adsorbent, the extract ispreferably pre-treated for complete fractionation, e.g., by vacuumconcentration or other techniques to remove organic solvent(s) in theextract or by sufficient dilution with water.

The extract used as a tea leaf extract preferably has a Brix degree of10° to 40°, particularly 20° or more.

The tea leaf extract thus prepared or a concentrate thereof may be useddirectly or in any form, for example, as a highly concentrated syrupextract blended with saccharides or as a dried product obtained byremoving the solvent from the tea leaf extract or a concentrate thereof.However, it is preferably dried in terms of shelf stability and safetyof organic solvent(s).

Such a dried product may be prepared in a standard manner; for example,by freeze-drying the extract or a concentrate thereof, or byspray-drying the extract or a concentrate thereof after being includedwithin a powdering substrate such as saccharides.

The present invention also provides carbon dioxide-containing drinkshaving foam-producing and foam-holding properties.

The carbon dioxide-containing drinks of the present invention may bealcoholic or non-alcoholic drinks. Examples include soda pops, lemonsoda drinks, cola drinks, carbonated fruit drinks, low alcohol drinks[which have an alcohol content of 12% or less, exemplified by sours(Japanese cocktails), chu-hi drinks (Japanese distilled spirit-baseddrinks) and cocktails], and non-alcoholic beers.

In a case where the carbon dioxide-containing drinks of the presentinvention are alcoholic drinks, there is no particular limitation on thetype of source liquor used to produce the drinks of the presentinvention. The source liquor may be a distilled liquor such as shochu(Japanese distilled spirit), whisky or other spirit, a fermented liquorsuch as sake, beer or wine, or a mixed liquor such as liqueur. Thefoam-holding agent of the present invention is preferred for use innon-effervescent distilled liquors or mixed liquors. The foam-holdingagent is also preferred for use in products based on shochu or spiritbecause they provide potential for a wider range of aromas. According tothe present invention, the foam-holding agent is also preferred for usein carbon dioxide-containing drinks having a taste and atmospheresuggestive of beer, as judged by their appearance. The foam-holdingagent of the present invention is preferred for use in low alcoholdrinks having an alcohol content of 12% or less, and particularly 6% orless.

In the present invention, the above tea leaf extract may be used inthese drinks, either alone or in combination, as appropriate. The tealeaf extract may be added depending on the intended state of foam; forexample, it is suitable to use the extract in an amount of 0.01% to 3%by weight, particularly preferably 0.02% to 1% by weight (calculated onthe tea-derived soluble solid content) relative to a product (drink) toensure a foam-producing property in terms of influences on costefficiency and aroma, etc.

Any type of foaming agent may be used in the present invention as longas it has a foam-producing property. For example, it is possible to usean emulsifier which is used in foods for the purpose of emulsification,dispersion, penetration, washing, whipping, dissociation, etc. Examplesof a foaming agent available for use in the present invention includeplant- or animal-derived saponin extracts, as well as chemicallysynthesized glycerine fatty acid esters, propylene glycol fatty acidesters, sucrose fatty acid esters and sorbitan fatty acid esters.

Examples of saponin extracts include a Quillaja saponaria extract,Sophora japonica saponin, enzyme-treated lecithins, enzyme-digestedlecithins, plant sterols, plant lecithins, sphingolipids, soybeansaponin, bile powder, animal sterols, tomato glucolipids, fractionatedlecithins, a Yucca foam extract, egg yolk lecithin, a barley huskextract, an enzyme-treated soybean saponin extract, tea seed saponin andbeet saponin, any of which may be used as long as it has afoam-producing property. They may also be purified before use.

To obtain a Quillaja saponaria extract, the bark of Quillaja saponaria(a member of the Rosaceous family) may be extracted with water. Theextraction may further be followed by purification using a porousadsorbent resin or the like to give a purified product.

To obtain Sophora japonica saponin, flowers and/or buds of Sophorajaponica (a member of the Leguminous family) may be extracted with wateror ethanol, and then purified.

To obtain enzyme-treated lecithins, lecithins may be treated with anenzyme.

To obtain enzyme-digested lecithins, lecithins may be digested with anenzyme.

To obtain plant sterols, oilseeds may be crushed and extracted with asolvent such as ethanol, followed by purification.

Plant lecithins can be obtained by separation from fats and/or oilsobtained from plant source materials such as oilseeds (e.g., soybean).

To obtain sphingolipids, rice bran or the like may be extracted withethanol or an organic solvent, and then purified.

To obtain soybean saponin, soybean (a member of the Leguminous family)may be crushed and extracted with water, ethanol or an organic solvent,followed by purification.

Bile powder can be obtained by powdering animal bile.

To obtain animal sterols, the unsaponifiable fraction of sheep's woolwax (lanolin) or fish oil may be hydrolyzed or extracted with an organicsolvent, followed by purification.

To obtain tomato glucolipids, leaves or whole plants of tomato (a memberof the Solanaceous family) may be extracted with an organic solvent andthen purified.

To obtain fractionated lecithins, lecithins may be extracted withethanol or an organic solvent, followed by fractionation andpurification.

To obtain a Yucca foam extract, roots of Liliaceae plants such as Yuccabrevifolia may be extracted with water.

To obtain egg yolk lecithin, hens' eggs may be extracted with polar andnonpolar solvents, followed by removal of water and the solvents fromthe extract.

Examples of glycerine fatty acid esters available for use includedecaglycerine monolaurate and decaglycerine monooleate. Such glycerinefatty acid esters may be prepared by reaction of glycerine with a fattyacid or by reaction of a fat or oil with glycerine.

Examples of propylene glycol fatty acid esters available for use includepropylene glycol alginate ester. Such propylene glycol fatty acid estersmay be prepared by esterification of propylene glycol with a fatty acid.In the case of preparing propylene glycol alginate ester, propyleneoxide and an alkaline catalyst may be added to alginic acid, followed byreaction at about 70° C. under pressure.

To prepare sucrose fatty acid esters, sucrose may be dissolved indimethylformamide, mixed with a fatty acid methyl ester, and then heatedunder reduced pressure in the presence of an alkaline catalyst to effecttransesterification.

To prepare sorbitan fatty acid esters, sorbitol and a fatty acid may beheated and reacted in the presence of an alkaline catalyst.

To prepare calcium stearoyl lactate, lactic acid may be concentrated togive polymerized lactic acid, followed by treatment with calciumstearate.

These foaming agents may be used alone or in combination, asappropriate. Also, these foaming agents may be added as appropriate forthe intended purpose and degree depending on criteria for use ofadditives; for example, it is preferable to use them in an amount of0.001% to 2% by weight, particularly 0.002% to 1% by weight (calculatedas an active ingredient) relative to a product.

The drinks of the present invention may further be supplemented with ahop extract.

The hop is a climbing perennial plant belonging to the Moraceae family.Strobiles of this plant may be extracted with a solvent (e.g., carbondioxide, water, ethanol) or further concentrated for use as a hopextract in the present invention. It is preferably used in an amount of1 to 30 ppm (calculated as the concentration of a hop-derived component)relative to a product.

The drinks of the present invention contain carbon dioxide and arecharacterized by continuously providing a refreshing quality and apleasant texture on the throat, not only at the beginning of drinking,but also over a period of time, because they have appropriate ranges ofcarbon dioxide-induced effervescence and foam-holding property. Thedrinks desirably contain carbon dioxide at an internal pressure rangingfrom 0.5 to 3.5 kg/cm² (at 20° C.) per drink, preferably 1.2 to 2.2kg/cm² (at 20° C.) per drink. Carbon dioxide can be contained to give adesired concentration or a desired gas pressure in a standard manner bydilution with high-pressure soda water into which carbon dioxide hasbeen previously dissolved, or by using a carbonator.

The drinks of the present invention may optionally be supplemented withvarious additives and/or source materials commonly used in drinkproduction. For example, it is possible to use food additives (e.g.,flavorings, acidulants), as well as source materials usually taken asfoods (e.g., saccharides, fruit juices, dairy products). Specificexamples include sugar, isomerized sugar, dextrin, citric acid, lemonjuice, grapefruit juice, orange juice, fermented milk, cow milk andconcentrated milk.

These additives and source materials may be added as appropriatedepending on the types of drinks. For example, sugars are preferablyadded in an amount of about 0% to 15% by weight per drink, flavoringsare preferably added in an amount of about 0% to 2% by weight per drink,and acidulants are preferably added in an amount of about 0% to 2% byweight per drink.

ADVANTAGES OF THE INVENTION

The foam-holding agent of the present invention can be used to produceeffervescent drinks or forming beverage which have excellentfoam-producing and foam-holding properties and also provide dense andsmooth-textured foam when compared to conventional effervescent drinksor forming beverage.

EXAMPLES

The present invention will be further described in more detail in thefollowing examples, which are not intended to limit the scope of theinvention.

Example 1 Preparation of Black Tea Extract

Black tea leaves were extracted with boiling water and concentratedunder reduced pressure to give a concentrate having a Brix degree of 24°to 26°, which was then mixed with sugar to prepare a black tea leafextract having a Brix degree of 62° (containing 12% by weight of solidextract derived from black tea leaves).

Example 2 Test for Foam-Producing and Foam-Holding Properties

1. Sample Preparation

White sugar was added to 90 ml grain spirit (alcohol content: 59%) togive a Brix degree of 4.5±0.1, to which citric acid and malic acid werefurther added to prepare a solution having a solid content of 0.2%.

Eight samples shown in Table 1 (Samples 1 to 8) were prepared bysupplementing the above solution with the black tea extract obtained inExample 1 (the same applying hereinafter), a hop extract (HASS HOPPRODUCTION, INC) or a Quillaja saponaria extract (MaruzenPharmaceuticals Co., Ltd.), either alone or in combination.

The resulting samples were each diluted with high-pressure soda water,into which carbon dioxide had been dissolved, to adjust the alcoholcontent to 5.3% and the internal carbon dioxide pressure to 2.2±0.2kg/cm² (at 20° C.), followed by filling into a 350 ml can for use in thefollowing test.

2. Test for Foam-Producing and Foam-Holding Properties

The whole volume of each sample prepared above was poured over a givenperiod of time (10 seconds) into a funnel fixed on the top of ameasuring cylinder. The total volume (ml) (sum of liquid and foamfractions) was measured immediately after completion of pouring and thenmonitored over time (at 0.5, 1, 2, 3, 4, 5 and 10 minutes).

The experimental samples and experimental glassware were allowed tostand overnight in a thermostatic chamber set at 20° C., and theexperiment was also performed at 20° C. Table 1 shows the resultsobtained. TABLE 1 Black tea Quillaja extract- saponaria- derivedHop-derived derived soluble solid component component contentconcentration concentration Sample (0.5 g/L) (0.005 ml/L) (0.035 ml/L) 0min 0.5 min 1 min 2 min 3 min 4 min 5 min 10 min 1 Yes Yes Yes 880 820800 750 710 680 640 520 2 Yes Yes No 740 600 540 360 350 3 Yes No Yes850 820 810 770 740 710 690 570 4 No Yes Yes 870 830 810 770 720 680 630470 5 Yes No No 740 500 360 350 6 No Yes No 680 350 7 No No Yes 860 830810 780 730 710 680 520 8 No No No 680 350

As shown in Table 1, Sample 3, containing both the Quillaja saponariaextract and the tea leaf extract, was confirmed to have an improvedfoam-holding property when compared to Sample 7 containing the Quillajasaponaria extract alone.

Moreover, the result of Sample 1 indicated that the sample containingthe tea leaf extract was excellent in effervescence and foam-holdingproperty even when further supplemented with the hop extract.

The above results indicated that the tea leaf extract provided anexcellent foam-holding property.

Example 3 Test for Foam Density

Each sample prepared in Example 2 was filled into a 120 ml small glassbottle and provided for use in this test.

Each sample (120 ml) was first cooled in a thermobath set at 10° C.Next, a funnel was placed on a transparency meter and the whole volumeof each cooled sample was poured over 5 seconds. After 30 seconds, acock of the transparency meter was opened to remove only the liquidfraction from the bottom, and the remaining foam fraction was measuredfor its height (cm). Ethanol (95%, about 500 μl) was then poured intothe transparency meter for the purpose of defoaming, and the resultingliquid was measured for its height (cm).

The following equation was used to calculate a foam density value.Foam density ratio=liquid height after defoaming (cm)/foam fractionheight (cm)

Table 2 shows the results obtained. TABLE 2 Liquid Foam height Quillajafraction after Foam Black tea Hop saponaria height defoaming densitySample extract extract extract (cm) (cm) ratio 1 Yes Yes Yes 30.5 10.40.34 2 Yes Yes No 26 8 0.31 3 Yes No Yes 32.5 10 0.31 4 No Yes Yes 309.5 0.32 5 Yes No No 6 No Yes No 7 No No Yes 31 8 0.26 8 No No No(Samples 5, 6 and 8 were excluded from comparison because of the resultsindicating that their foam-producing and foam-holding properties werenot effective.)

As shown in Table 2, the foam density was higher in Sample 3 containingboth the Quillaja saponaria extract and the black tea extract whencompared to Sample 7 containing the Quillaja saponaria extract alone.

It was also indicated that, when compared to Sample 4, the foam densitywas higher in Sample 1 which was further supplemented with the black teaextract.

The above results indicated that the tea leaf extract provided thick andsmooth-textured foam.

Example 4 Sensory Test

The eight samples prepared in Example 2 were tested while cooling toabout 5° C. to 10° C.

Three panelists specializing in aroma evaluated and scored the samplesfor their effervescent quality in the mouth and their texture on thethroat on a scale of up to 5 points. The scores given by these threepanelists were summed for each sample (maximum 15 points) and used todetermine the superiority. The evaluation was conducted in an objectivemanner by hiding the ingredient composition of each sample. Table 3shows the results obtained. TABLE 3 Quillaja Black tea Hop saponariaTotal score in Sample extract extract extract sensory test 1 Yes Yes Yes4 4.3 4.5 12.8 2 Yes Yes No 3.7 4 4.5 12.2 6 No Yes No 3 3.9 3.5 10.4 4No Yes Yes 2.4 3.5 4 9.9 3 Yes No Yes 3.5 3 3 9.5 5 Yes No No 2.8 3.7 39.5 7 No No Yes 2.2 4 3 9.2 8 No No No 2 3 2 7

The samples containing the black tea extract were confirmed to besuperior in sensory aspects because such samples had a fine and pleasanteffervescence in the mouth and provided a better texture on the throat.

In particular, it was indicated that the combined use with the hopextract was particularly effective.

Example 5 (Chu-Hi Drink)

A solution was prepared in the following ratio and diluted to a desiredvolume with high-pressure soda water to make a chu-hi drink. Theinternal carbon dioxide pressure was adjusted to 2.2 kg/cm². Sugar 30 gCitric acid 1.5 g Grain spirit (alcohol 59%) 90 ml Quillaja saponariaextract 0.03 ml (calculated as a (Maruzen Pharmaceuticals Quillajasaponaria- co., Ltd.) derived component) Black tea extract 3.5 g(soluble solid (Example 1) content: 0.42 g) Flavorings 2 ml Total 1000ml

Example 6 (Chu-Hi Drink)

A solution was prepared in the following ratio and diluted to a desiredvolume with high-pressure soda water to make a chu-hi drink. Theinternal carbon dioxide pressure was adjusted to 2.2 kg/cm². Sugar 30 gDextrin 10 g Citric acid 1.5 g Grain spirit (alcohol 59%) 90 ml Quillajasaponaria extract 0.03 ml (calculated as a (Maruzen Pharmaceuticals)Quillaja saponaria- derived component) Black tea extract 3.5 g (solublesolid (Example 1) content: 0.42 g) Hop extract 0.003 ml (calculated as ahop-derived component) Flavorings 2 ml Total 1000 ml

Example 7 (Carbonated Fruit Drink)

A solution was prepared in the following ratio and diluted to a desiredvolume with high-pressure soda water to make a carbonated fruit drink.The internal carbon dioxide pressure was adjusted to 2.2 kg/cm². Sugar80 g Citric acid 2 g Grapefruit juice 10 g (5-fold concentrated)Quillaja saponaria extract 0.03 ml (calculated as a (MaruzenPharmaceuticals) Quillaja saponaria- derived component) Black teaextract 3 g (soluble solid (Example 1) content: 0.36 g) Flavorings 2 mlTotal 1000 ml

Example 8 (Non-Alcoholic Beer)

A solution was prepared in the following ratio and diluted to a desiredvolume with high-pressure soda water to make a non-alcoholic beer. Theinternal carbon dioxide pressure was adjusted to 2.2 kg/cm².Fructose/glucose liquid sugar 5 g Dextrin 20 g Malt extract 5 g (San-EiGen F.F.I., Inc.) Citric acid 0.01 g Lactic acid 0.4 g Quillajasaponaria extract 0.03 ml (Maruzen Pharmaceuticals) Black tea extract1.0 g (soluble solid (Example 1) content: 0.12 g) Hop extract 0.03 mlFlavorings 2 ml Total 1000 ml

All of the drinks prepared in Examples 5 to 8 were found to have asufficient foam-holding property and to be satisfactory with regard tosafety, taste, aroma and other properties required for foods.

1. A foam-holding agent which comprises a water and/or ethanol extractof tea leaves.
 2. The foam-holding agent according to claim 1, which isobtained by concentrating a water and/or ethanol extract of tea leaves.3. The foam-holding agent according to claim 1, wherein the concentrateobtained by concentrating a water and/or ethanol extract of tea leaveshas a Brix degree of 10° to 40°.
 4. The foam-holding agent according toclaim 1, wherein the tea leaves are those of black tea, green tea oroolong tea.
 5. A carbon dioxide-containing drink characterized bycomprising: (A) a foaming agent; and (B) a water and/or ethanol extractof tea leaves.
 6. The drink according to claim 5, which furthercomprises a hop extract.
 7. The drink according to claim 5, wherein thetea leaves are those of black tea, green tea or oolong tea.
 8. The drinkaccording to claim 5, wherein the internal pressure of carbon dioxide is0.5 to 3.5 kg/cm² (at 20° C.).
 9. The drink according to claim 5,wherein a fermented grain liquor is not used as a source material. 10.The drink according to claim 5, which is a soda pop, a lemon soda drink,a cola drink, a carbonated fruit drink or a low alcohol drink.
 11. Thedrink according to claim 5, which is a low alcohol drink having analcohol content of 12% or less.
 12. A method for producing a carbondioxide-containing drink, which comprises preparing a drink blended witha foaming agent and a water and/or ethanol extract of tea leaves, andincorporating carbon dioxide into the resulting drink.